Upright space-dividing wall panels are conventionally utilized in offices and the like for dividing large work spaces into smaller work areas. The wall panels are conventionally in the range of 1' to 5' wide, and have a height which varies approximately from desk height to ceiling height. These panels typically have one or both opposed side faces thereof covered by fabric sheets which are stretched across the panel faces and secured along the panel boundaries or edges. The securement of the fabric along the panel edges is conventionally accomplished by several known techniques, most of which employ a gripping member for holding the fabric edge to maintain the fabric in a stretched or taut condition as it extends across the panel side face. In one conventional securing technique, the panel is provided with an outwardly opening retaining channel along each edge thereof, which retaining channel is configured to permit an edge portion of the fabric to be folded therein, with a retaining member such as an elongate flexible endless band or similar such element inserted into the retaining channel to hold the fabric therein while at the same time maintaining the fabric in a stretched or taut condition. This structure, however, and the method of securing the fabric to the panel, is costly and time consuming with respect to required assembly time and labor.
Reference is made to U.S. Pat. Nos. 4 084 366 and 4 213 493, both owned by the Assignee hereof, which disclose conventional methods and structures for securing edge portions of a fabric to a space-divider panel, such structures corresponding substantially to those described above.
Accordingly, it is an object of this invention to improve upon the prior structures and methods as described above, and more specifically to provide an improved method and apparatus for securing a fabric to a space-divider panel so that the fabric can be maintained in a desired taut condition over the panel side face while permitting the edge of the fabric to be easily and economically secured, and at the same time permitting relatively easy removal of the fabric when and if desired for permitting replacement thereof. More specifically, it is an object of this invention to provide an improved method and apparatus for permitting edge portions of a flexible fabric sheet, as positioned over an enlarged side face of a wall panel, to be efficiently and substantially automatically secured around the perimeter or edges of the wall panel while requiring only minimal manual labor and supervision, and at the same time providing the desired degree of stretch or tautness in the fabric so as to provide for proper covering of the panel side face.
It is also an object of the present invention to provide an improved method and apparatus for securing a fabric to a panel, as aforesaid, which permits the fabric to be secured to and stretched across the side face of the panel, including wrapped around the panel corners, while providing an overall desirable appearance and providing improved appearance and handling of the fabric where it wraps around the corners.
A further object of the invention is to provide an improved method and apparatus for securing a fabric to a panel, as aforesaid, wherein the securing arrangement utilizes an adhesive for securing the fabric edge portion within a retainer channel associated with the panel so that separate retainer strips or bands are not required.
It is a further object of the invention to provide an improved method and apparatus for securing a fabric to a panel, as aforesaid, which enables the fabric to be subsequently removed from the panel if desired, such as for replacements of the fabric, with the replaced fabric then being securable to the panel utilizing a conventional securing technique, such as by employing an elongate endless elastic band.
Summarizing the method and apparatus of the present invention, a panel is provided with a rectangular frame having elongate frame elements which extend along the edges of the panel, with each frame element having one or more elongate fabric-receiving channels. A film or bead of meltable adhesive extends interiorly along each of the channels. The panel is disposed on a panel transfer assembly so that one side face of the panel is oriented upwardly, and a fabric sheet is disposed to extend across the upwardly-facing side face of the panel with edge portions of the sheet overlying the frame elements. The panel is relatively moved past a pair of opposed roller assemblies disposed on opposite sides of the panel, which roller assemblies engage and force the edge portions of the fabric, on opposite sides thereof, into respective fabric-receiving channels. Substantially simultaneously therewith the edge frame elements are also relatively moved past a heating element, such as an induction heater, which effects rapid melting of the adhesive as the fabric is being forced into the channels by the rollers. The inward forcing of the fabric into the channels by the rollers also effects stretching of the fabric across the panel to achieve the desired tautness. Shortly thereafter the panel edge frame elements are relatively moved under a cooler such as an air jet which effects rapid resolidification of the adhesive, and securement thereof to the edge portions of the fabric. After the rollers have relatively moved throughout the length of one opposed pair of side frame elements, then the panel is subjected to the same process along the remaining pair of side frame elements so as to effect securement of the fabric along all four sides of the panel.
Other objects and purposes of the invention will be apparent to persons familiar with structures of this general type upon reading the following specification and inspecting the accompanying drawings.